An air filter is known from the market which has a housing with a raw air inlet and a clean air outlet. A round filter element is arranged between the raw air inlet and the clean air outlet. The round filter element comprises a filter medium for purifying raw air. The housing has a housing container with an installation opening for the round filter element. The installation opening can be closed by a housing cover. In particular, the housing container can be separated from the housing cover for replacement of the round filter element.